New waste-based supplementary cementitious materials: Mortars and concrete formulations

The compressive strength behavior of cement mixtures produced with wood ash was investigated. This ash was characterized to determine its potential as supplementary cementitious materials (SCMs) in Portland Cement (PC) as pozzolanic material (WFA) and as active aggregate (HWA). By assuming the pozzolanic mineral addition content in Portland Cement PC IV as reference, as well as considering WFA with the highest pozzolanic potential, we developed the SCM binder fraction. This was achieved by replacing up to 50 wt% of PC, combining WFA and pozzolan with Portland Cement PC V. By defining the binder fraction along with HWA characterization, concrete compositions replacing up to 30 vol% of the aggregate fraction with HWA were established. The use of WFA reduces the compressive strength, while HWA decreases the elasticity modulus of the produced concretes. Ecoconcrete containing similar to 17.2 wt% of waste exhibited over 40 MPa after 28 days of curing and high durability. (C) 2019 Elsevier Ltd. All rights reserved.